Lighting paintings and the like with the help of a lighting assembly comprising a lighting rail and a series of separate lighting devices attached to the lighting rail is known. It is also known to combine such a lighting rail with a suspension means for the paintings. The paintings can then be movably attached to the lighting rail with the help of suspension elements, which can have the shape of a hook or a clamping block, and to which, for example, a suspension wire or suspension rod for the painting can be attached.
In the lighting assembly the lighting devices are clamped on or in the rail in such a manner that the contact part of the lighting device is held urged against the conducting strip which is arranged in the lighting rail. The lighting device usually has an elongated arm of considerable length so as to enable the lamp to illuminate the painting from a direction which is advantageous for exposition purposes. A consequence hereof is that the lighting device exerts a considerable vertical moment on its area of attachment to the lighting rail. It therefore often happens that the contact part of the lighting device slips upwards or sidewards (in a vertical plane) along the contact area of the conducting strip. As a result of that, the electrical contact may be severed and/or the orientation of the elongated arm changed, due to which the lighting device will stop functioning and/or the view on a series of initially parallely arranged lighting devices will be disturbed.